I am currently working with Professor Woodward Fischer at Caltech investigating the origin of photosynthesis and the associated oxygenation of the surface ocean and atmosphere during the Paleoproterozoic. We are examining two Agouron Drilling Project cores, GEC and GTF, to better understand the development of photosynthesis and the timing and manner of the major oxidation of our planet.
Previously, I have worked with Professor Jessica Whiteside at Brown University on another, later climatic upheaval: the Devonian glaciation and major mass extinction. We used the mid-Devonian sedimentary record from an ancient rift basin in Scotland (the Caithness flagstones) to investigate preserved climatic and ecological proxies. I measured bulk and compound-specific (leaf wax alkanes from the emerging terrestrial plants) carbon, hydrogen and nitrogen isotopes, and determined the abundances of longer chain alkanes. There was a clear climatic control on the lacustrine ecology occuring in rhythmic cycles, likely reflecting orbital (Milankovitch) cycles.
Additionally, I have participated in an NSF-funded REU (Research Experiences for Undergraduates) program at the University of Southern California working with Frank Corsetti and Dave Bottjer. We measured the sulfur isotopic signals from carbonate-associated sulfate (CAS) during the Triassic-Jurassic mass extinction 200 million years ago, which supported the hypothesis that changes in the ocean circulation played a role in the mass extinction. I also have worked in Professor Tim Herbert’s lab, analyzing O2 isotopes and foraminifera species from anoxic ocean regions to help reconstruct Pliocene climate. Further, I contributed to a project for Professor Jessica Whiteside by preparing Pennsylvanian samples from the Kinney Quarry, New Mexico, for carbon, nitrogen and hydrogen isotopic analysis.